Circuit breaker mechanism



, 1940 5 Sheets-Sheet l May 20, 1941. H. G. MacDoNALD CIRCUIT BREAKER MECHANISM Filed June 2l May 20, 1941 H. G. MacDoNALD 2,242,916

CIRCUIT BREAKER MECHANSM Filed June 2l, 1940 5 Sheets-Sheet 3 May 20, 1941. H. G. MacDoNALD CIRCUIT BREAKER MECHANISM Filed June 2l, 1940 5 Sheets-Sheet 4 WlTN ESSES:

Patented May 20, 1941 UNITED STATES PATENT OFFICE CIRCUIT BREAKER MECHANISM Pennsylvania Application June 21, 1940, Serial No. 341,613

(Cl. E300-89) Y 16 Claims.

The invention relates to circuit breakers of the type adapted for high speed reclosing operation. Cir-cuit breakers of this type usually embody a non-trip-free tripping means arranged to initially trip the breaker without releasing the breaker from its operative relation or connection to the closing means thereby permitting the breaker to be reclosed instantly without waiting for a resetting or retrieving operation. The

breaker also embodies a trip-free tripping means a,

which is effective to trip the breaker free of the closing means if the fault is still present upon reclosure of the circuit. It is sometimes necessary to close the circuit breaker manually as, for example, during maintenance, or when the power operated closing means becomes inoperative, and for this purpose the circuit breaker is provided with a manually operable closing device.

For safety of both apparatus and operator it is important that the circuit breaker should always be under the control of the trip-free tripping means whenever the breaker is being manually operated. To .this end an object of the present invention is the `provision of a circuit breaker of the class described with a means which is automatically eiective to place the breaker under the control of the trip-free tripping means whenever the circuit breaker is being manually operated or manually closed.

The novel features that are considered characteristic of the invention are set forth in particular in the appended claims. The invention itself, however, both as to structure and operation together with additional objects and advantages thereof will be best understood from the following detailed description of one embodiment thereof when read in conjunction with the accompanying drawings, in which:

Figure 1 is a side elevational View, partly in section, of a circuit breaker operating mechanism embodying the features of the present invention, the mechanism being shown in the latched closed position with the closing solenoid deenergized;

Fig. 2 is a plan view of the circuit breaker operating mechanism shown in Fig. 1;

Fig. 3 is a fragmentary sectional View taken substantially along the line III-III of Fig. 2 showing the trip coil plunger and the rocking trip bar for operating either the trip free tripping latch or the non-trip-free tripping latch of the mechanism;

Fig. 4 is a partly schematic View of the operating mechanism and `circuit breaker showing the relative position of the parts immediately following a tripping operation by the non-tripree latch;

Fig. 5 is a side elevational View of the operating mechanism in the open position with the manually operable closing device mounted in position for closing the breaker, the breaker being shown somewhat schematically as in Fig. 4;

Fig. 6 is a View similar to Fig. 5 except that it shows the mechanism at the beginning of a tripping operation after the breaker has been closed by the manual closing device;

Fig. 7 is a front elevational View, partly in section of the manually operable closing device; and

Fig. 8 is a side elevational View, partly in section, of the manually operable Vclosing device.

The present invention is illustrated as applied to a circuit breaker operating mechanism of the type disclosed in Patent 2,150,587, issued to A. J. A. Peterson, March 14, 1939, and assigned to the assignee of the present invention. It is to be understood, however, that the principle of the invention is also applicable to any circuit breaker operating mechanism or system wherein tripping of the breaker in response to predetermined abnormal conditions is normally arranged to be effected by a non-trip-free tripping means so as to permit an instantaneous or high speed reclosure of the breaker, and wherein a trip free tripping means is also provided for effecting tripping of the breaker in response to the predetermined conditions at other times as, for example, When the fault is still present upon automatic reclosing of the breaker.

Referring to the drawings, the reference numeral 9 indicates generally a fabricated steel frame for supporting the various parts of the circuit breaker operating mechanism.

A closing solenoid Il is mounted on the lower portion of the frame 9 and comprises a movable core I3, a cooperating stationary core I5 and an operating winding l1 which, when energized, pulls the movable core I3 downwardly to effect a closing operation of the circuit breaker.

A lever mechanism of the trip-free type indicated generally at I9 is mounted on the upper portion of the frame and this mechanism serves to normally connect the circuit breaker with the closing solenoid. The lever mechanism comprises a closing lever 2l which is pivoted at its right-hand end on the upper portion of the frame 9, and a breaker lever 23 which is pivoted at its left-hand end to the free end of the closing lever 2l. The closing lever 2| consists of a pair of spaced parallel outer levers 25 (Fig.

2) which have their right-hand ends pivoted about a common axis by means of a pair of aligned pivot studs 2l carried by two spaced vertical plates il@ which form a `part ci the frame 9. The breaker lever 23 consists of a pair of spaced parallel inner levers tl which have their leithand ends pivoted on a pivot pin 33 carried by and connecting the free ends of the outer levers 25. The inner levers Si which form 'the breaker lever are spaced so as to be movable into the space between the outer levers 25 which iorm the closing lever. The right-hand end of the breaker lever 23 carries a trip-free roller which is mounted on `a pin carried by and connecting the free ends of the inner lever 3l.

The circuit breaker which may be of any suitable construction is shown schematically in Figs. 4 and 5 as comprising stationary main and arcing contacts 31 and 39 and a movable bridging contact assemblage M which consists oi a laminated main bridging contact 4S for bridging the main stationary contacts 37, and a pair of spring biased movable arcing contacts i5 for engaging the stationary arcing contacts 39. The arcing contacts are arranged to engage prior to engagement of the main contacts during closing or" the circuit breaker and to separate following separation of the main contacts during opening of the circuit breaker. The movable contact assemblage is carried by a rod 46 which is connected to the mid-portion of the breaker lever 23 through the agency of a pivoted lever il and an operating rod fit, the lower end of the opera-ting rod 4Q being pivotally connected to the breaker lever 23 by means or" a pivot pin 5l which extends between the inner levers Si. The circuit breaker is biased to open circuit position by an opening spring 53.

The breaker lever 23 is biased upwardly by the opening bias of the circuit breaker, and the tripfree roller 35 carried by the free end of the lever 23 is normally engaged and releasably held in a position of alignment with the pivot axis 2 of the closing lever 2| by a trip-free latching mechanism indicated generally at disposed adjacent the right hand end or the frame. When the trip-free roller 35 is held in latched position, the breaker lever 23 is operatively connected to the closing lever 2l for movement thereby. The closing lever 2i is connected to the movable core I3 of the closing solenoid l by means of a pair of connecting links 5l, and the free end of the closing lever is adapted to be releasably held in closed position as shown in Fig. 1 by means of a non-trip free latch mechanism indicated generally at 59 disposed adjacent the left hand end of the frame and which engages a non-trip free roller El carried by the pivot pin The closing lever 2i is biased in a clockwise direction about its xed pivot axis 2l by means of a pair of retrieving compression springs 63 which are disposed between each of the outer levers 25 and an upper supporting plate of the frame 9.

When the trip-free roller t5 carried by the free end of the breaker lever 23 is released by a releasing operation of the trip-free latch mechanism 55, the operative connection between the circuit breaker and the closing lever 2l is released and the breaker is moved to open circuit position under the influence of its opening spring free of any restraint by the closing means. The opening movement of the circuit breaker causes the breaker lever 23 to rotate in a counterclock- Wise direction toward the open position about the pivot pin 3S which is held down by the nontrip free latch mechanism The breaker lever 23 during a portion of its opening movement, effects an automatic releasing operation of the non-trip-free latching mechanism 59 to cause release of the lfree end or the clos'ng lever 2E. For this purpose the breaker lever provided with a projecting pin 65 adjacent its pivoted end which, during a portion of the opening movement of the lever 23 engages and rotates a pivoted bell crank releasing lever El to effect release of the non-trip-iree latching mechanism. 59 and consequently the free end of the closing lever 2i. rThe bell crank releasing lever 6l is pivcted on a pivot pin 9? and is biased in counterclockwise direction by means of a coil spring G3 interposed between the upper supporting plate of the frame and a projection on the lever 6l.

When the free end of the closing lever 2l is thus released by the releasing lever, the retrieving springs S3 rotate the closing lever 2| in a clockwise direction about its fixed pivot axis 21, and since the pivot pin 5i which connects the breaker operating rod i9 with the breaker lever 23 becomes stationary when the breaker reaches open position, the clockwise rotation of the closing lever 2i by the retrieving springs eliects a clockwise rotation or the breaker lever 2li about the pivot pin 5i as a center to return the trip free roller 35 into latching engagement with the tripfree latch mechanism At this point the two levers 2l and 23 are in the position shown in Fig. 4 and since the trip-free roller 35 is relatched by the trip-free latch mechanism 55, the breaker lever 23 is again operatively connected to the closing lever 2l and through the same to the movable core i3 of the closing solenoid.

When the closing solenoid I! is energized, the two levers 2! and 23 are rotated in a counterclockwise direction about the common axis of the pivot studs 2l' and the trip-free roller 35 to the closed position shown in Fig, 1 to eiiect closing of the circuit breaker. When the two levers reach the closed position the non-trip-free roller 6l carried by the pin 33 of the closing lever is reengaged and latched by the non-trip-iree latch mechanism 59.

The circuit breaker may also be tripped open by a releasing operation oi the non-trip-free latching mechanism 5t. A releasing operation of the non-tri -free latch mechanism allows the circuit breaker to be moved to open position by its opening spring and this movement causes the two levers El and 23 to rotate in a clockwise direction about the common axis of the pivot studs 2l and the trip-free roller 35 to the open position shown in Fig. 4. in this instance, however, the circuit breaker remains operatively connected to the closing lever il! and through the saine to the movable core of the closing solenoid il so that the breaker can be immediately reclosed by energizaticn of the closing solenoid Il.

The trip-free latch mechanism E5 (Fig. l) comprises a main latch $9 pivoted on a pivot pin 'Il carried by a part of the frame and is biased by means of a spring '13 to a latching position in which it engages and restrains the trip free roller 35 in the position shown in Fig. l. A block T5 carried by the frame serves as a Seat for one end of the latch spring '13, and this block is provided with a surface 'il which forms a stop to prevent movement of the latch 69 beyond its latching position. in order to hold the latch 59 in latching position against the upward bias exerted on the breaker lever 23, an auxiliary latch 19 is provided. The latch 19 is pivoted by means of a pin 8| carried by a portion of the frame and is biased to latching position by means of a light spring 83. The nose of the latch 19 is provided with a substantially right angled notch 85 for engaging the upper corner of the main latch 69. The auxiliary latch 19 in latching position effectively locks the main latch 69 in its latching position. The auxiliary latch 19 is adapted to be moved in a clockwise direction about its pivot axis 8| to effect a releasing operation of the latch mechanism by a tripping means which will be hereinafter described.

When the auxiliary latch 19 is released, the trip-free roller 35 moves upwardly under the opening bias of the breaker forcing the main latch 69 in a clockwise direction until the roller 35 clears the nose of the latch. The spring 13 then returns the main latch 69 to latching position. The main latch 69 is provided with a rounded nose to allow the roller 35 to force the latch back and clear the same during resetting or retrieving of the breaker lever 23 and the roller 35. As soon as the trip-free roller 35 has cleared the nose of the latch 69 during a retrieving operation, the spring 13 returns the latch 69 to latching position and the auxiliary latch 19 returns to its latching position to engage and hold the main latch 69,.

In order to ensure complete retrieving of the breaker lever 23 and the trip-free roller 35 t0 latching position, it is necessary that the auxiliary latch .'9 be held in its released position free of the main latch 69 until the trip-free roller has been returned to its latching position. Other- Wise the trip-free roller would jam against the rounded nose of the main latch 69 during a retrieving operation. For holding the auxiliary latch 19 in. its released position during the release and retrieving of the breaker lever 23, there is provided a holding lever 81 pivoted on the pivot pin 8| and biased in a clockwise direction by a spring 89 which is slightly stronger than the latch spring 83. The lever 81 is provided with one extending arm 9| which lies in the path of the final retrieving movement of the free end of the breaker lever 23. When the tripfree roller 35 is in latching position, the free end of the breaker lever 23 holds the lever 81 down in an inoperative position to allow the auxiliary latch 19 to assume its latching position. However, when the trip-free roller moves upwardly following a tripping operation by the latch mechanism 55, the holding lever 81 rotates in a clockwise direction, and a cross pin 93 carried thereby engages and holds the auxiliary latch 19 in its released position until the trip-free roller has been retrieved to its latching position.

The non-trip-free latch mechanism 59 is substantially similar to the trip-free latch mechanism previously described. The latch mechanism 59 comprises a main latch 95 pivoted on the pin 91 carried by part of the frame, and the latch is biased by means of a spring 99 to latching position in which it engages and restrains the nontrip-free roller 6I carried by the closing lever 2|. A block IOI carried by the frame serves as a support for one end of the spring 99, and this block is provided with a stop surface |03 (Fig. 4) for preventing movement of the latch 95 beyond its latching position. The main latch 95 is held in latching position by means of an auxiliary latch |05. The auxiliary latch is pivoted on a pin |01 carried by a portion of the frame, and the latch |05 is biased to latching position by means of a light spring |09. The nose of the latch |05 is provided with a substantially rectangular notch for engaging the upper corner of the main latch to lock the main latch in latching position, and the main latch 95 is provided with a rounded nose to permit it to be forced back and cleared by the non-trip-free roller 6| during closing movement of the closing lever 2|. In order to permit the closing lever 2| to be moved to its completely closed position and to be relatched by the latch mechanism 59, there is provided a holding lever ||3 which is similar to the holding lever 81 of the trip free latch mechanism 55. The holding lever I|3 is pivoted on the pin |01 and is biased in a counterclockwise direction by a spring I|5 which is slightly stronger than the latch spring |09. The lever I3 is provided with an arm II1 which extends into the path of the final closing movement of the free end of the closing lever 2|. When the closing lever 2| is in the closed position shown in Fig. 1, the lever I|3 is held down in an inoperative position, to permit return of the auxiliary latch |05 to latching position. However, when the free end of the closing lever 2| moves upwardly following tripping operation of the latch member |05, the holding lever ||3 rotates in a counterclockwise direction and a cross pin |20 carried thereby engages and holds the auxiliary latch |05 in released position clear of the main latch 95 until the closing lever 2| has been returned to the fully closed and latched position by the closing solenoid Both of the latching mechanisms 55 and 59 are adapted to be operated by a single trip coil I|9 (Fig. l) The trip coil ||9 is mounted on a portion of the frame beneath the trip-free latch mechanism 55 and is provided with a trip plunger I2I. The operating winding of the trip coil is adapted to be energized in response to predetermined overload conditions in the circuit controlled by the breaker or in response to any other abnormal condition under which tripping of the breaker is desired. Energization of the trip coil causes upward movement of the trip plunger I2I. A rocking trip bar |23 (Fig. 3) rests freely on a plate |25 carried by the frame above the trip coil I I9. The plate |25 is provided with an opening |21 for receiving the upper end of the trip plunger |2| and with suitable guides |29 for guiding the trip bar |23 and for preventing longitudinal and lateral displacement thereof. The trip plunger I2 I, when moved upwardly, engages the under side of the trip bar |23 to cause rocking movement of the bar about whichever end is held against movement. The auxiliary latch 19 of the trip-free latch mechanism 55 is disposed over one end of the trip bar |23 and the free end |3| of a pivoted bell crank lever |33 is disposed over the opposite end of the trip bar |23. The bell crank lever |33 is pivoted intermediate its ends on the pivot pin 8| carried by the frame 9, and the upper end of the bell crank lever is pivotally connected by means of a pivot pin |31 to the right-hand end of a horizontal connecting link |39. The left-hand end of the connecting link |39 engages the upper end of the releasing lever 61 through the agency of a pin and slot connection MI.

If the trip plunger I2I is moved upwardly at a time when the bell crank lever |33 is prevented from moving in a clockwise direction, the upward movement of the trip plunger I2I Will cause the rocking trip bar |23 to rock about its end Which engages the free end |3| of the bell crank lever |33 to elfect upward movement of the auxiliary latch 'I9 to cause release of the trip free latch mechanism 55. On the other hand, if the trip plunger ifi! is moved upwardly at a time when the auxiliary latch 'i5 is prevented from moving in a clockwise direction, the upward movement of the plunger |2i causes the rocking trip bar |23 to rock about its end which engages the auxiliary latch l to effect clockwise rotation of the bell crank lever |33. The clockwise rotation of the bell crank lever |33 moves the horizontal connecting link |39 towards the right and rotates the releasing lever 61 in a clockwise direction to effect release of the latch |05 and the non-trip free latch mechanism 59. If neither the bell crank lever |33 nor the auxiliary latch l5 are held against movement, the upward movement oi the plunger |2| eiects release of both the trip free and the non-trip free latch mechanisms.

In order to permit the circuit breaker to be automatically reclosed as quickly as possible following each initial opening operation caused by an overload or other abnormal condition, tripping oi the breaker is normally arranged to be effected by the non-trip-free latch mechanism 59, providing the closing solenoid l l is in deenergized condition and hasI been deenergized for a sufficient length of time for there to be no substantial magnetic ux present in the solenoid. When the breaker is tripped by the non-trip-free latch mechanism, it is moved to open position without releasing the operative connection between the breaker and the closing lever or solenoid so that the breaker can be quickly reclosed without Waiting for any resetting or retrieving operation. i

This permits the circuit breaker to be reclosed in the shortest possible time. The closing solenoid may be arranged to be energized substantially simultaneously with the trip coil or during the initial portion of the opening movement oi the breaker so that it will have developed suiilcient ux to halt opening movement of the breaker and begin to reclose the breaker as soon as the arcs drawn between the contacts of the breaker have been extinguished, without allowing the breaker to continue to the full open circuit position. However, ii the overload or abnormal condition occurs at a time when the solenoid is in an energized condition or when there is still an appreciable quantity of residual magnetic iiux present in the solenoid, it is important that the breaker be tripped open by means of the trip-free latch mechanism 55 in order to permit high speed opening of the breaker unretarded by any opposing force or magnetic drag of the closing solenoid il.

In order to provide for ripping of the breaker by the proper latch mechanism in accordance with the condition oi the closing solenoid there is provided a means responsive directly to the magnetic iiux of the closing solenoid for automatically selecting the proper latch mechanism 55 or 59 for operation by the trip coil IIS. The automatic selecting means comprises a magnetic selector lever M5 which is pivoted intermediate its ends on the pivot pin 'i i. The lever 45 has a yoke-shape portion Uil of magnetic material which is disposed directly over the winding Il and the magnetic frame of the closing solenoid so as to be traversed and influenced by a portion of the magnetic flux of the solenoid. The selector lever |545 is biased in a clockwise direction to a normal unattracted position by means of a pair of springs I4?. which are interposed between the yoke portion |41 of the lever and the 75 upper end plate of the solenoid Il. The righthand arm |53 of the selector lever |45 is provided with an end or bar |55 which is disposed directly above the auxiliary latch member T9 of the trip-free latch mechanism 55.

When the solenoid I I is deenergized and when there is substantially no magnetic flux present in the solenoid which would retard opening movement of the closing lever 2|, the springs |49 maintain the selector lever |-i5 in the unattracted position shown in Figs. 1 and 4, in which position the projection |55 thereof engages and holds the auxiliary latch T9 of the trip-free latch mechanism 55 in latching position. The springs |49 are of sufficient strength to overcome the force of the trip plunger l2 and hold the auxiliary latch 'i9 in latching position to prevent operation of the trip-free latch mechanism 55 by the operation of the trip coil H9. If an overload condition occurs under these conditions, that is, with the magnetic selector lever in the unattracted position, the upward movement of the trip plunger |2| causes the trip bar |23 to be rocked about the end thereof engaged by the latch 19, to rotate the bell crank lever |33 in a clockwise direction. The clockwise rotation oi the bell crank lever |33 moves the horizontal link |38 toward the right to cause clockwise rotation of the releasing lever 6'1 and consequently release of the non-trip-free latch mechanism 59, It will thus be seen that the occurrence of an overload when the selector lever |45 is in the unattracted position causes tripping oi the breaker by means of the non-trip-free latch mechanism 59 only.

When the solenoid is in energized condition or Whenei-'er there is any appreciable magnetic flux present in the solenoid which would retard opening movement of the closing lever 2i, the inagnetic flux maintains the selector lever |45 in the attracted position shown in Fig. 5. In the attracted position of the magnetic selector lever M5, the projection |55 thereof is maintained in the raised position clear oi the auxiliary latch 19 so as to permit operation of the trip-free latch mechanism 55. In its raised position the projection engages a lug |51 carried by the horizontal link 39 to prevent right-hand movement of the link |59 and consequently clockwise movement oi the bell crank lever |33. Ii an overload condition occurs under these conditions7 that is, when the magnetic selector lever is in the attracted position due to the presence of magnetic flux in the solenoid H, the upward movement of the trip plunger EE! will cause the trip bar |23 to rock about the end thereof which engages the arm |S| of the bell crank lever |33, to cause the trip bar to move the auxiliary .latch l5 to released position since the bell crank lever |33 is prevented from being moved in a clockwise direction. Thus, the upward movement of the plunger lai under these conditions effects a tripping operation of the areaker by means of the trip-free latch mechanism 55.

The pin and slot connection 54| between the left-hand end of the horizontal link |39 and the releasing lever @il serves to allow the releasing lever i5? to be automatically moved to the released position during` the upward movement of the breaker lever 23 to effect release of the closing lever and retrieving of the trip-free roller 55, even though the link is prevented from being moved towards the right by the engagement ,f the projection i555 with the lug |51.

In order to prevent the magnetic selector lever from forcing the auxiliary latch 'i9 down to latching position in engagement with the main latch 69 at times when the trip-free roller 35 is away from latching position, the arm |53 of the lever |45 is provided with an interlock projection |59, which is adapted to be engaged by a short arm |6| of the holding lever 81 when the holding lever 81 is in the raised position, as shown in Fig. 5.

The circuit breaker and mechanism may be controlled by any suitable circuit breaker reclosing control system such, for example, as the system disclosed in Patent No. 2,150,584, issued to J. B. MacNeill, March 14, 1939, and assigned to the assignee of the present invention.

The circuit breaker operating mechanism thus far described is of the same construction as discosed in the aforementioned Patent No.

' 2,150,587 to A. J. A. Peterson.

It is sometimes necessary to close the circuit breaker by hand as, for example, during servicing or maintenance of the breaker or when the power operated closing means becomes inoperative for any reason. For `this purpose the circuit breaker mechanism is provided with a manually operable closing device which is adapted to be removably mounted on the left-'hand end of the circuit breaker operating mechanism as shown in Fig. when it is desired to manually close the breaker. Referring to Figs. 5, 6, l and 8, the manually operable closing device consists of a jack of the screw type which when mounted on the circuit breaker mechanism engages a portion of the frame at one end and engages the movable end of the closing lever 2| at its other end. The construction of the manually operable closing device is best shown in Figs. '1 and 8, and the device comprises a housing or base |65 upon which is rotatably mounted a pair of parallel shafts |61 and |69. The shafts |61 and |69 are rotatably mounted at their lower ends in suitable bearings provided in the housing |65 and are retained in mounted position therein by collars fixed to the shafts above the housing and by fastening nu-ts |1| which thread onto the lower ends of the shafts, the fastening nuts |1| being retained in proper position by cotter pins |13. The shafts |61 and |69 are connected for simultaneous rotation together in the same direction by means of gears |15, |11 and |19 which are disposed within the hollow housing |65. The gear |15 is rigidly secured to the shaft |61 and engages the intermediate gear |11 which is rotatably mountedl upon a centrally disposed stub shaft |8|. The intermediate gear |11, in turn, meshes with the gear |19 which is rigidly secured to the shaft |69. The shafts |61 and |69 are braced at their upper ends by a cross bar |83 which is provided with lbearing openings at each end for fitting over the upper reduced ends of the shafts |61 and |69, the shafts being free to rotate in the bearing openings. The cross bar |83 is retained in mounted position by retaining nuts |85 which are held in the proper position by cotter keys |81.

The upper portions of the shafts |61 and |69 are threaded in the same direction to provide worms |69. and mounted upon and threadedly engaging the worms |89 are a pair of traveling nuts |9|. Each of the nuts |9| is provided with a pair of laterally projecting cylindrical lugs |93 which are adapted to engage in semi-cylindrical recesses |95 provided in the bifurcated ends |91 of the outer levers 25 of the closing lever 2| when the manually operable closing device is mounted in position on the circuit breaker operating mechanism.

The base of the manually operable closing device is provided with a boss |99 intermediate the shafts |61 and |69 and this boss carries a cylindrical lug 20| which is retained in position by a setscrew 202. The ends of the lug 20| are adapted to seat in appropriate recesses 293 (Figs. 1, 2 and 5) provided in a pair of spaced plates 205 which form a part of the mechanism frame 9.

The traveling nuts |9| are prevented from rotating with the shafts |61 and |69 by means of a pair of guide rods 201 which are secured at their upper ends to the cross bar |83 by means of nuts 208. The guide rods 201 extend through openings provided in ears 2M which are formed integral with the nuts |9|, and the lower ends of the rods 291 engaged in openings provided in washers 2 |2 which are rotatably mounted on the shafts |61 and |69.

The shafts |61 and |69 which are geared for simultaneous rotation together are rotated by means of an operating handle 2|3 which is adapted t0 drive the shaft |61 through the agency of a ratchet and pawl device. A ratchet wheel 2|5 is rigidly secured to the shaft |61 immediately above the housing |65, and the operating handle 2|3 is provided with a hub 2|1 which is rotatably mounted on the shaft 61. The ratchet Wheel 2 |5 is nested within the hub 2|1 as shown in Fig. 7, and the hub 2 |1 is provided with a reversible pawl (not shown) which is adapted to engage in notches formed between teeth 2|9 of the ratchet wheel whereby the ratchet wheel and shaft |61 may be selectively rotated by the handle 2|3 in either direction.

If it is desired to manually close the circuit breaker, the manually operable closing device is mounted in position on the left-hand end of the circuit breaker operating mechanism as shown in Fig. 5 with the lug 20| seated in the recesses 203 of the frame 9 and the lugs |93 of the traveling nuts |9| seated in the semi-circular recesses |95 of the closing lever 2|. To manually close the circuit breaker the opera-ting handle 2 |3 is manually rotated back and forth to effect progressive rotation of the shaft |61, this movement being transmitted to the shaft |69 so that both of the shafts |61 and |69 are rotated together, and in a direction to cause downward movement of the nuts |9|, thereby moving the closing lever 2| in a counterclockwise or closing direction to effect closing of the breaker. The worm portions |89 of the shafts |61 and |69 are designed so as to be self-locking thereby permitting the breaker to be moved to any adjusted position and remain in such a position without holding the operating handle 2|3. rllhis permits the breaker to be serviced or adjusted by maintaining the contacts in any desired position.

As has previously been described, tripping of the circuit breaker in response to an overload or other abnormal condition is normally arranged to be effected by the non-trip-free latching mechanism 59 in order to permit the breaker to be reclosed as quickly as possible on the first reclosure. For safety of both apparatus and operator, however, it is very important that the circuit breaker should be disposed for trip-free operation, that is, be capable of being opened in response to operation of the trip coil irrespective of the position of the closing lever whenever the breaker is being operated by the manually operable closing device. Otherwise the breaker may be manually closed and held yclosed against a short circuit or fault condition. In accordance with the invention, a device is provided which derstood that various changes in the structural details thereof may be made without departing from the spirit of the invention. It is desired, therefore, that the appended claims be given the broadest reasonable interpretation permissible in the light of the prior art.

I claim as my invention:

1. In combination, a circuit breaker, power operated closing means for closing said breaker, a non-trip-free tripping means eiective to trip said breaker in response to predetermined abnormal conditions at certain times, trip-free tripping means effective to trip said breaker in. response to predetermined abnormal conditions at other times, manually operable means operable to cause closing of said breaker, and means operable to automaticallyplace said breaker under the control of said trip-free tripping means whenever the breaker is being closed in response to operation of said manually operable means.

2. In combination a circuit breaker, power operated closing means for said breaker, a nontrip-free tripping means by which said breaker is tripped in response to predetermined abnormal conditions if said predetermined abnormal conditions occur at times when the breaker has been standing in one position for more than a predetermined length of time, trip-free tripping means by which said breaker is tripped free in response to predetermined abnormal conditions at other times, a manually operable closing device for closing said breaker, and means operable to automatically place said breaker under the control of said trip-free tripping means whenever the breaker is being operated by said manually operable closing device. l 3. In combination, a circuit breaker, closing means movable to close said breaker, power operated means operable when energized to cause said closing means to close the breaker, a nontrip-iree tripping means normally arranged to cause opening of the breaker in response to predetermined abnormal conditions in the circuit and leaving said breaker connected for closing by said closing means, trip-free tripping means operable in response to predetermined abnormal conditions to cause opening of the breaker irrespective of the position of the closing means, said trip-free tripping means being operable if said predetermined abnormal conditions occur when said power operated means is in energized condition, manually operable means operable to cause said closing means to close the breaker, and means operable to cause the breaker to be tripped free of the closing means if the predetermined abnormal conditions occur when the breaker is operated by said manually operable means.

4. In combination, a circuit breaker, closing means movable to close said breaker, power opera-ted means operable when energized to cause said closing means to close the breaker, a nontrip-free tripping means normally arranged to cause opening of the breaker in response to predetermined abnormal conditions in the circuit and leaving said breaker connected for closing by said closing means, trip-free tripping means operable in response to predetermined abnormal conditions to cause opening of the breaker irrespective oi the position of the closing means, said trip free tripping means being arranged to trip the breaker if the predetermined abnormal conditions occur witliin a predetermined length of time after a tripping operation by said nontrip-free tripping means, manually operable means for operating the breaker, and means op-y erable to automatically place said breaker under the control of said trip-free tripping means whenever the breaker is operated by said manually operable means.

5. In combination, a circuit breaker, power operated closing means for said breaker, tripping means for effecting opening of said breaker independently of the condition of said closing means, additional tripping means for effecting opening of said breaker only under certain conditions of said closing means, manually operable means for operating said breaker, and means operable to automatically place said breaker under the control of said rst-mentioned tripping means when said breaker is operated by said manually operable means.

6. In combination, a circuit breaker, operating means movable to close said breaker, power operated means for causing said operating means to close the breaker, la non-trip-free tripping means normally arranged to cause opening of said breaker in response to predetermined abnormal conditions and leaving said breaker operatively connected for closing by said operating means, trip-free tripping means operable to cause opening of said breaker in respon-se to predetermined abnormal conditions irrespective of the position of said operating means, said trip-free tripping means being eieotive to cause opening of the breaker if said predetermined abnormal conditions occur at times when said power operated means is applying a force opposing opening of the breaker, a manually operable closing device operable to cause said operating means to close said breaker, and means operable to automatically place said breaker under the control of said trip-free tripping means when said breaker is being operated by said manually operable device.

'7. In combina-tion, a circuit breaker, operating means movable to close the breaker, power operated means operable to `cause said operating means to close the breaker, a non-trip-iree tripping mcans opera-ble to cause openil'ig of said breaker in response to predetermined abnormal conditions if said predetermined abnormal conditions occur at times when said power operated means does not oppose opening oi the breaker, said breaker remaining operatively connected for closing by said operating means when tripped by said non-trip-free tripping means, trip-free tripping means operable in response to predetermined abnormal conditions to cause opening oi' said breaker irrespective of the position of said operating means, said trip-free tripping means being arranged to cause opening of said breaker in response to said predetermined abnormal conditions if said predetermined abnormal conditions occur at times when said power operated meansI exerts a force opposing opening of the breaker, manually operable means for moving said operating means to operate the breaker. and means for `causing said breaker to be tripped free of said operating means if said predetermined abnormal conditions occur at a time when said breaker is being operated by said manually operable means.

8. In combination, a circuit breaker, an operating member movable to close the breaker, electrically operated closing means operable to move said operating member to close the breaker, nontrip-free tripping means operable in response to predetermined abnormal conditions in the circuit to cause opening of said breaker only if said closing means is deenergized, trip-free tripping means operable in response to predetermined abnormal conditions in the circuit to cause opening of the breaker irrespective of the position of the operating member and independently of tile energized condition of the closing means, means responsive to the condition of the closing means for causing tripping of tbe breaker in response to said predetermined abnormal conditions to be eiected only by said non-trip-iree tripping means when said closing means is deenergized, and by said trip-free tripping means when said closing means is energized, manually operable means operable to move said operating member to operate the breaker, and means operable to cause tripping of tbe breaker in response to said predetermined abnormal conditions to be effected by said trip-free tripping means if said predetermined abnormal conditions occur when said breaker is operated by said manually operable device.

9. In combination, a circuit breaker, an operating member movable to close the breaker, electrically operated closing means operable to cause said operating member to close the breaker, non-trip-ree tripping means operable in response to predetermined abnormal conditions in the circuit to cause opening of the breaker only if said closing means is deenergized, trip-free tripping means operable in response to predetermined abnormal conditions in the circuit to cause opening of the breaker irrespective of the position of said operating member and independently of the energized condition of said closing means, means responsive to the condition of said closing means for placing said breaker under tbe control or said non-trip-ree tripping means only when said closing means is deenergized and under the control of said trip-free tripping means Wnen the closing means is energized, a manually operable closing device operable to cause said operating member to close tbe breaker, and an element engageable by said manually operable closing device for automatically placing the breaker under the control of said trip-free tripping means when the breaker is being closed by said manually operable closing device.

l0. In combination, a circuit breaker, an operating member movable to close tbe breaker, electromagnetic closing means for moving said operating member to close the breaker, non-tripfree tripping means operable in response to predetermined abnormal conditions in the circuit to cause opening of the breaker only if said electromagnetic means is in deenergized condition, trip-free tripping means operable in response to predetermined abnormal conditions in the circuit to cause opening of the breaker irrespective of the position of said operating member and independently of the energized condition of the closing means, an element responsive to the condition of said closing means for normally placing said breaker under the control of said non-tripfree tripping means only when said closing means is deenergized and under the control of said trip-free tripping means when said closing means is in energized condition, a manually operable device operable to move said operating member to close the breaker, and a member engageable by said manually operable device for causing said element to place said breaker under the control of said trip-free tripping means when said breaker is being operated by said manually operable device.

11. In combination, a circuit breaker, an operating member movable to close the breaker, power operated closing means for moving said operating member to close the breaker, non-trip-ree tripping means operable in response to predetermined abnormal conditions in the circuit to cause opening of tbe breaker only if said closing means is deenergized, trip-free tripping means operable in response to predetermined abnormal conditions in tb. circuit to cause opening of the breaker irrespective or" the position of said operating member and independently of tne energized condition of said closing means, means operable to place said breaker under the control of said non-trip-ree tripping means only when said closing means is in deenergized condition and under the control of said trip-free tripping means Whenever said closing means exerts a force opposing opening of tlie breaker, a manually operable device operable to move said operating member to close the breaker, and means engageable by said manually operable device for automatically causing said breaker to be placed under the control of said trip-free tripping means whenever said breaker is being operated by said manually operable device.

l2. In combination, a circuit breaker, an operating member movable to close the breaker, electromagnetic closing means for moving said operating member to close the breaker, non-tripfree tripping means operable in response to predetermined abnormal conditions in th circuit to cause opening oi the breaker only when said closing means is in deenergized condition, trip-free tripping means operable in response to predetermined abnormal conditions in the circuit to cause opening of the breaker irrespective of tbe position of said operating member and independently of the energized condition of said closing means, means responsive to the magnetic ux of said closing means for normally placing the breaker under the control of said non-trip-ree tripping means only when there is no substantial magnetic ux present in said closing means and for placing the breaker under the control of said trip-free means Whenever there is any substantial magnetic flux present in said closing means, a manually operable closing device, and a member engageable by said manually operable closing device for automatically causing the breaker to be placed under the control of said trip-free tripping means Whenever the breaker is being operated by said manually operable device.

13. In combination, a circuit breaker biased to open position, an operating member movable to close the breaker, power operated closing means operable to move said operating member to close the breaker, a first latch normally and releasably connecting the breaker to said operating member, said latch being releasable to cause opening oi the breaker free of said operating member and closing means, a second latch for releasably holding said breaker closed, trip means operable in response to predetermined conditions for releasing said latches, means responsive to tbe condition of said closing means for causing said trip means to erlect release of only said second latch if tbe predetermined conditions occur when said closing means is in deenergized condition and for causing said trip means to effect release of said first latch if the predetermined conditions, occur when said closing means exerts any substantial force opposing opening of the breaker, a manually operable device operable to move said operating member to close the breaker, and means comprising a member engageable by said manually operable device ior automatically causing the operation of said trip means to effect release of the rst latch if the predetermined conditions occur when the breaker is being operated by said manually operable device.

14. In combination, a circuit breaker biased to open position, an operating member movable to close the breaker, electromagnetic closing means operable to move said operating member to close the breaker, a rst latch normally and releasably connecting said breaker to said operating member, said latch being releasable to cause opening of the breaker irrespective of the position of saidv operating member, a second latch for releasably holding the breaker closed, trip means operable in response to predetermined conditions for releasing said latches, a member responsive to the magnetic flux of said closing means operable to normally prevent release of said first latch by said trip means when there is no substantial magnetic flux in said closing means and operable to permit release of said rst latch when there is any substantial magnetic flux in said closing means, a manually operable closing device operable to move said operating member to close the breaker, and means engageable by said manually operable device for automatically causing said magnetically responsive member to permit release of said rst latch whenever the breaker is being operated by said manually operable device.

l5. In combination, a circuit breaker, an operating member movable to close the breaker, closing means operable to move said operating member to close the breaker, a non-trip-free tripping means normally effective to cause opening of the breaker upon the occurrence of predetermined abnormal conditions, and a trip-free tripping means operable to cause opening of the breaker irrespective of the position of said operating member in response to predetermined abnormal conditions if said predetermined abnormal conditions occur at any time when a force is applied to said operating member opposing opening of the breaker.

16. In combination, a circuit breaker operating mechanism comprising an operating member movable to close the breaker, power operated means operable to move said operating member, non-trip-free tripping means effective to trip said breaker in response to predetermined abnormal conditions at certain times, trip-free tripping means effective in response to predetermined abnormal condition at other times to cause opening of the breaker irrespective of the position of said operating member, a manually operable closing device removably mountable on said operating mechanism for moving said operating member to close the breaker, and means operable to automatically place said breaker under the control of said trip-free tripping means whenever said manually operable closing device is in mounted position on said operating mechanism.

HOWARD G. MACDONALD. 

